W116 brake upgrade - PeachParts Mercedes-Benz Forum

Alec300SD · #1 02-15-2018, 11:55 PM

‘Stormcloud’ recently got a four-corner brake upgrade as part of getting her roadworthy.
Previously, I changed over to DOT 5 brake fluid, replaced the brake reservoir and the grommets for the reservoir.

The rear brake upgrade from stock involved using rear wagon calipers from a W123 wagon
(same size caliper but with a larger piston = more clamping force),
ceramic pads (better braking and less brake dust), and stainless brake hose (firmer pedal).

The rear brakes were replaced with the parts harvested from ‘Rena 2.0’ before she was sent to the crusher
'Rena 2.0' braking news

Rear brake upgrade parts list:
1) Rotors - OP rotors (405 33 147) (MB 115 423 04 12),
2) OP ceramic pads (D-8031-OC) (MB 001 420 45 20),
3) Right rear ATE W123 wagon caliper (ATE 210058) (MB 123 420 12 83)
4) Left rear ATE W123 wagon caliper (ATE 210057) (MB 123 420 11 83)
5) caliper locking plates (from the Textar parking brake kit),
6) and Deerfield Precision Braided Stainless Brake Hoses C-D, E, S-T-(Rear) (BSL-381105) (MB 126 428 03 35).

The rear left caliper had been sticking as the inner side of the rotor was heavily scored.
The rear left parking brakes had lost all of the friction material.

I couldn’t find the MB parking brake kit (MB 126 420 01 20) I had purchased.
I just installed the best two parking brake shoes that hadn’t made it to the
PNP recycling bin after ‘Rena 2.0’ had a set of NOS Textar parking brakes installed.

My independent mechanic let me borrow his spring insertion tool which made switching out the rear left parking shoes a much easier job.
I’ve since found my new MB parking brake kit and will install it when time permits.

Alec300SD · #2 02-15-2018, 11:58 PM

The front brake upgrade does require that you use at least 15inch rims due to clearance issues from the use of larger rotors and calipers.
‘Stormcloud’ has 16inch Lorinser rims on APEX racing studs.
The front brake upgrade from stock involved using late W126 front rotors (larger rotors),
late W126 front calipers (larger calipers and larger pistons = more clamping force),
late W126 front dust shields (air cooling via built -in front ducting),
larger ceramic brake pads, and stainless brake hoses.

Front brake upgrade parts list:
1) MB late W126 front brake shields (MB 126 421 09 20)
2) MB late W126 front rotors (MB 126 421 05 12 64)
3) Front right rebuilt ATE caliper (OP 612 33 533) (MB 126 420 07 83)
4) Front left rebuilt ATE caliper (OP 612 33 534) (MB 126 420 06 83)
5) Akebono ceramic pads (EUR1072) (MB 005 420 45 20)
6) Deerfield Precision Mercedes-Benz Stainless Brake Hoses Early (Front) S, SL, D (BSL-38513) (MB 123 428 05 35).

The front brake shield has the stamped recess to secure the original W116 brake hose guide bracket...but the bolt hole is absent.
A one-quarter inch hole was made to allow reuse of the W116 brake hose guide bracket.

The brake sensor harness plastic sheathing has cracked and will be replaced.
l have a pair of PNP late W126 brake sensor harnesses that may fit through
the metal tube on the original W116 brake sensor harness guide.
Once I track them down, I’ll post a picture if they do fit.

The front wheel bearings looked okay, and still had adequate amounts of the green MB wheel bearing grease.
I will repack them later when I get the green MB grease.

The left front copper radio noise suppressor is missing and the left front
plastic clip for the brake sensor harness has cracked and will need replacing as well.

DOT 5 brake fluid was used to bleed the brake lines and the brakes were bedded in.
The brake upgrade went smoothly and is pretty much a bolt-on process (other than drilling the one hole in the front brake dust shield).

Alec300SD · #3 02-16-2018, 12:28 AM

The folks at Deerfield Precision provide excellent customer service.
I was impressed with the front and rear stainless brake hoses I installed on ‘Rena 2.0’.
Even though I had a one new Febi rear set of W116 rubber brake hoses and
one new ATE front set of W116 rubber brake hoses on hand,
I ordered two additional rear sets for my W116s (before sending ‘Rena 2.0’ to the crusher).

Alas, W116 front stainless brake hoses were not available from Deerfield Precision...at that time.
I did save the rear stainless brake hose set from ‘Rena 2.0’…giving me three rear sets.

Unfortunately, the front stainless brake set from ‘Rena 2.0’ was not usable in either W116,
as the W126 17mm hex fitting is too large for the 14mm hex receptacle of the W116 bracket.

After obtaining instructions on how to return the extra third rear brake hose set,
I inquired if I could pay extra to have two custom made sets of front W116 stainless brake hoses made.

They said yes, and asked me to send the measurements or an old hose as a template.
I returned the extra third set and enclosed one of the new ATE front W116 hoses as a template.
I received an email notification that the front W116 stainless brake hoses were being added to their product list,
and a photo of the new hose alongside of the template I provided.

I promptly ordered two sets of the new front W116 stainless brake hoses for my W116s.

More photos below - the forum limits you to five attachments per post.

jtwoods4 · #4 03-31-2019, 08:22 PM

Alec, what a great project and what a nice upgrade. Great job.

Squiggle Dog · #5 03-31-2019, 11:11 PM

Really cool! I probably would have done this if I didn't like wheel covers so much and 15" wheel covers weren't so rare and expensive.

Alec300SD · #6 11-11-2019, 11:46 PM

In July ‘Desert Rose’ finally got new rear wheels, and the same rear brake upgrade that ‘Stormcloud’ received.

Parts used: 07/13/2019 Rear brake upgrade.
Deerfield Precision SS rear brake lines BSL-381105
ATE rear left wagon caliper (123-240-11-83)
ATE rear right wagon caliper (123-240-12-83)
MB rear rotors (126-423-00-12-64)
MB Brake shoes (126-420-01-20)
Motor Medic DOT 5 Brake fluid (UPC 078698119281)
MB lug nuts M12 X 1.5 X 52 (126-401-06-70)
MB hub caps (107-400-00-25)
McGard Wheel Locks (Radius Seat Lug Bolt) M12 X 1.5 - Modified (shank shortened to match the shank length of MB lug bolts)
Rear OP Ceramic Brake Pads (D 8031 OC) (UPC 826732914602)
MB 15inch Bundt Rims (126-400-22-02)
Pirelli P600 235/60R15 tires

Front brake upgrade for 'Desert Rose' will also take place at a later date, after the brake parts and two Pirelli P600 235/60R15 tires are acquired for the front axles.
As you see in the first photo, 'Desert Rose' had a bit of sagging of the rear suspension.
Just finishing up some rear suspension work on 'Desert Rose' and will post on a separate thread.

RobertFini · #7 11-15-2019, 06:53 AM

How do these upgrades affect stability at the limit - any sense of impending lockup in the rear? Any issues with modulation? Can the master cylinder handle the additional volume required by the larger pistons on the rear calipers?

Alec300SD · #8 11-15-2019, 12:42 PM

No issues with panic stops and no indication of lockup on either 'Stormcloud' or 'Desert Rose'.
No ABS on either vehicle, so no pulsing of brakes.

Brake fluid reservoir capacity is more than sufficient to supply the additional brake fluid used by the master cylinder with the upgrade.
Negligible increase in brake pedal travel.

This was a relatively mild upgrade from stock, using heavier duty stock calipers from other MB models.

greazzer · #9 11-15-2019, 01:05 PM

Great write-up Alec. I've got my backing plates and calipers back from the powder coater. Just looking for a nice afternoon now ...